const Person = function ( firstAndLast ) {
  let firstName = [ ...firstAndLast.split( ' ' ) ][ 0 ];
  let lastName = [ ...firstAndLast.split( ' ' ) ][ 1 ];
  this.setFirstName = ( first ) => firstName = first;
  this.setLastName = ( last ) => lastName = last;
  this.setFullName = full => {
    const fullName = [ ...full.split( ' ' ) ];
    firstName = fullName[ 0 ];
    lastName = fullName[ 1 ];
  };
  this.getFullName = () => firstName + ' ' + lastName;
  this.getFirstName = () => firstName;
  this.getLastName = () => lastName;
};

const bob = new Person( 'Bob Ross' );
bob.setFullName( "Haskell Curry" );
console.log( bob.getFullName() );
